rifling

[Daniel]

 Who can refresh the rifling in a .62 cal swamped barrel?  I bought a gun that
needs some help.

[WadePatton]

You can. 

when in doubt, lap it out!

Or maybe you were looking to hire someone...I don't know about that method. 

[Daniel]

Going to try to lap it out. Got told to put valve compound on a
patch and try. How would you do it?

[smokinbuck]

Daniel,
I would cast a lead slug in your barrel and put the valve grinding compound on that. Doing that gives you a "cast" of the existing rifleing to follow as you draw the the lead slug through the bore. You can get various grades of compound to bring a bore to pretty good condition, depending on what you are starting with.
Mark

[Acer Saccharum]

Maybe all you need to do is to smooth up the bore. I'd pull the plug, brush it out well, and see how a patched ball goes thru. If the patch tears, you've got roughness, and the gun will never shoot well until the patches exit the bore whole.

Lapping compound on a patch might shine the bore, but it won't take out deeply rusted pits. Work from the breech end, as working grit from the muzzle end will bell the bore out, causing accuracy loss.

If you really need to re-cut, Bob Hoyt can refresh/recut rifling. He's a genius with this kind of thing.

[Daniel]

The grooves are full of crud. I am slowly getting them cleaned of and there are no pits
so far. Looks like the fellow never cleaned his guns.

[Daniel]

this barrel has been coned to btw.

[WadePatton]

Get the crud out and test as Acer suggests. If it's all smooth enough, then proper lapping/freshing shouldn't be necessary.  

besides, it's been coned.  

oh...(longer post modified)

you'll have to cast your lap at the breech, coning will prevent you from using the muzzle-end for casting of the lap.

best of luck.

[Acer Saccharum]

Do all your work from the breech end, so you don't bell the bore just before the cone starts.

[Daniel]

I'm trying. Never pulled a breech plug. Got a lot of crud out and I think I
need to send it out.

[Gene Carrell]

A quick method of "gitting the crud out" is to scrub with RB-17. It will take you to solid steel within 30 minutes or so and you will know what you have to work with.

[Daniel]

I have done all I can. Thank you all for the help.
Going to send it to Robert Hoyt.

[blaksmth]

If you decide to lap the barrel after making the lead lap,  trim the end of the lead and do not remove the lap from the barrel , leave some of the lap in the barrel, if you remove it you need to make a new lap as the rifelings may be off some.
but push the lap out of barrel a little more than half was and cut a couple of groves in the lap to hold the lapping compound.

when lap becomes loose put a rod against the lead and give it a little tap with a hammer to swell the lap some and check for tight spots, work them untill they are better.

[Dphariss]

The lap simply has to be indexed to the barrel before removing. Mark the end where the top flat (or whatever) is as the lap is exiting the barrel.

Dan